Adventure fiction. Jack, Peggy, Nora and Mike are four children who, in their first adventure together, run away from strict guardians after their parents are thought to have been killed in a place crash. The children make way for a secret island on their huge expanse of property, and together they make a new home constructed with the branches of a willow tree. The much-loved "living house" is just one of the highlights of the first book, The Secret Island, which was originally written as a serial and, in 1938, published as a full length novel.